Syphon server receives glitchy texture

[pizthewiz]

One issue I’ve run into with Screener (app to stream display capture via Syphon) is that the content Syphon receives is sometimes garbled. After some number of relaunches of Screener.app or Syphon Recorder.app, things start working again but I can’t quite figure out what the root cause is – it looks a bit like this:

And a video of the good-goes-bad can be seen here.

Is there some handshake I could be missing or other possible causes for this?

[vade]

Do you get the same behavior from the v002 Screen Capture Plugin -> Syphon Server in QC?

[pizthewiz]

No dice with the Screen Capture plugin, something wacky seems to be happening even internally, let alone piping the result to Syphon:

In the case of Screener, it’s built-in GL preview of the captured IOSurfaceRef shows the expected behavior, but I seem to be messing up something when sending the resulting texture to the Syphon server. It is almost as if some GL state is bleeding somewhere and when things go pear shaped, some number of app relaunches (both Screener and Syphon Recorder) are required to sort it out.

• This reply was modified 7 years, 1 month ago by pizthewiz. Reason: mangled the image tag and link

[vade]

Er. that one doesn’t work in anything past 10.6, as the GL screen capture path was removed. I meant the version included in Media Tools, that you based your code off of 🙂

[pizthewiz]

Ahh yes that seems reasonable – I grabbed the source, converted the project to ARC and it seems to run without a hitch through start/stop (which I’m guessing is equivalent to app relaunch, though it would have the same GL context) and Syphon Recorder.app relaunches.

So I’m guessing something in my GL use in Screener.app isn’t entirely kosher…

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